One of the world’s leading brain injury experts last night welcomed the development. Dr Ganesh Bavikatte, consultant and clinical lead in rehabilitation medicine at The Walton Centre NHS Foundation Trust, said: “If the reports are true, this is absolutely good news.”

But he warned: “The road to recovery will be long, and filled with uncertainty and frustration.”

Dr Bavikatte added: “It will be difficult for his friends and family. Severe brain injury causes significant physical, cognitive and psychosocial impact on the person involved and their loved ones.”

He said it could take weeks to bring the star fully out of his coma. Then he will need careful monitoring and therapy to assess the extent of the damage to his brain.